Propeller for aeroplanes



Jan. 12 192e. 1,569,800

T. A. DICKS PROPELLER FOR AEROPLANES Filed Deo. 21.4 1922. s men-sheet 2 FIGA.

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W/TNESSES Jan. 12 1926. 1,569,800 f T. A. DlcKs PROPELLER FOR AEROPLANES wv v/v for? w/ -rNEssEs www? 1 A @Wk-.03mg

A ent constructe consist -ally of the hubs.

Patented Jan. 12, 1926.

UNITED STATES PATENT OFFICE.

s THOMAS A. DICKS, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO STANDARD STEELv i PROIPELLEB COMPANY, 0F PITTSBURGH, PENNSYLVANIA, A CORPORATION OF DELAWARE.

PnornLLEn ron AnRoPLNEs.

Application lcd December 21, 1922. Serial No. 608,192.

To all 'u1/mm it may concern y .Be it known that I, THOMAS A. Dicks, rcsiding. at Pittsburgh, in the county of Allegheny and State of Pennsylvania, a subject of Great Britain, have invented or discovered certain new and useful Improve- `nents in Propellers for Aeroplanes, of which improvement the following is aspecification.

The invention described herein relates to certain improvements in hubs for connectin the driving shaft to the blades of a prope ler for aero lanes. These hubs as at presof a tubular body portion and socketed projections arranged radi- It has heretofore been the practice to manufacture such hubs with the body portions and the projections in which the sockets are formed integral. In the manufacture of such hubs a piece of metal was forged to the approximate external shape and the body portion bored entirely through for the reception of one end of the shaft and the radial .projections bored to to form sockets forthe reception of the 'ends of the propeller blades. After the boring of the body portion and projections has been effected the parts must be finished internally so as-to insure close fitting with the shaft and Shanks of the blades and also externally. As the body portions and radial projections are inte ral' the boring and finishing operations lnvolve repeated handling of the structure. The present method i of construction avoids in its manufacture the loss of metal removed in boring at the eX-y pense of the manufacturer.

The invention described herein has for its object a construction wherein a tubular bod)7 portion and a cross arm having means at its end for engaging the shanks of the blades are separable and wherein the said" arm may be formed of semicilcular sections. further object of the invention to form vbody portion and arm in sections, the arm being constructed to clamp the sections of the body portions together. The invention is hereinafter more fully described and claimed.

In the accompaying drawing which forms apart of these specifications, Fig. 1 'is a section l elevation of a propeller hub embodyi g improvements claimed herein; Fig. .2 is a sectional view on a plane indicated by the line II-.II, Fig. 1; Fig.3 is a sectional view 0n a 'plane indicated bythe line HI-A lt is a III, Fig. 2; Fig. 4 is a plan view ofone of the arm sections; Fig. 5 is an end view of the body portion; Figs. 6 and 7 are views similar to Figs. 4 and 5 showing a modification in the construction of the arm and body portions; Fig. 8 is a sectional View showing the body portion of the hub and the arm formed ing removed.

In the construction shown in Figs. l, 2 and 3, the tubular body portion of thel hub 1 is formed tapering internally for the reception of the correspondingly shaped end of the shaft and with a longitudinal groove 2 for the reception of the key or feather on the shaft. Externally the body portion is provided with peripheral seats 4 and 5 for the arm to the ends of which the blades of theV propeller are secured. The seats or bearing portions 4 and 5'are spaced distances apart dependent on the diameter of the arm, and the surfaces of the seats are made irregular incross-section so as to insure a tive driving connection between the portion and the arm. As for example, in the construction shown in Figs. l to. 5, the seats' are made polygonal in cross section and the opening through the arm is correspondingly shaped, while in the form shown in Figs. 6 and 7 the seats are formed with the plurality of longitudinal ribs 6 and the Walls of the opening through the arm are grooved for the reception of the ribs.

The cross arm is provided at its ends with suitable means such as sockets for the reception and engagement with the Shanks of the blades and midway of its lengt-h an opening is formed through the' arm for the reception of the body portion of the hub. The walls of the opening through the arm are constructed as hereinbefore stated to fit,

tion'V of' the body' portion of 'the hub` theV peripheral contours of these openings-cor responding to the peripheral contours of f o're described. The'positipns of the members forming 'the arm longitudmally of the 1n sections; and Fig. 9 is an end view of the hub and arm, one section of the arm be.

.10|` -the seats on the body portion as hereinbe V collar 9 integralgwith the a nut 10 screwingon to the outer end of the also by preference by nular recesses f ception OfenIargements or heads 18 on the shanks the abutments on the body portion of the hub` are determined by body portion and body portion. In order to increase the are'a of contact of the members on the seats, flanges 11 ane formed around the openings therethrough as shown in Figs. 1, 3,4 and 6, Said flanges also serving to increase the longitudinal strength of the members. It is preferred to interpose rings 12 between the flanges 11 and the collar 9 and nut 10 respectively, and it is preferred that the flanges and the surfaces of the rings bearing thereon should be so bevelledthat the rings will tend to against the seats on the body portions.

The members forming the arm are hel together around the Shanks 13 of the blades by means of rings 14 screwing onto the threaded portions 15 of the members and rings 16 screwing onto said' members adjacent to the ends t ereof as shown in Figs. 1 and 2. While any suitable means. may be employed for holdingv the shanksfrom lon 'tudinal movement in the sockets formed y the members when placed together it is preferred to form an ,127 in the members for the rev,Shanks of the b ades. In order to prevent any longitudinal movement of the shanks of the blades when engaged by the arm sections the Shanks are formed with abutments a for the ends of the arm sections, and the heads or enlargements 18 on the Shanks and the complementary walls of the recesses 17 in the arm sections are so beveled or inclined as indicated at b that when the arm sections are drawn together around the Shanks will be drawn firmly `against the ends of the' arm sections, as clearly shown in Figs. 1 and 2. While the grip of the members 011 the shanks would pro ably be suicientto prevent any turning of the Shanks in the sockets, it is preferred to employ pins 19 passing through the ,walls of the members into the heads 18 and held in position by the rings 14.

It is characteristic of the improvements claimeds herein that practically. all the stresses due to the centrifugal action of the blades are sustained by the arm or the members. forming the arm. The membersforming the arm can be formed to a proximately finished shape and size by rop forging them, greatly reducin Vthe cost of manufacture. A

The body portion of hubs for propellers are subjected rincipally to stresses operatingat an ang e to each other. .One set of stresses being those arising from the transmission ofmotion from the shaft to the blades can be termed circumferential stresses a while the other stresses vvhichfare by far the greatest to which .the hub` is subjected will force the flanges inwardly tion a tubular are due to the centrifugal force and there bein two oppositely disposed blades there two sets of oppositely acting stresses tending to tear the arms from the body poi'- tion and to rupture the latter. As in the improved construction the body portion of the hub is not subjected to these centrifugal strains and as the circumferential or ltransmitting strains do not tend to pull the body portion apart, such body portion may be made in two semicircular sections or meinbers, 20 and 21, as shown in Figs. 8 and 9. These sections or members may be brought to approximate shape and size by drop forging or' by any other suitable method and in the finishing or machining operations seats or bearings 4 and' for the arm are forme/d on the sections and yalso a shoulder or abutment 22 against which the ring or band 23 will bear, this band serving as a support or bearing as against the movement in one rdirection of the members of the arm on the body portion, movement of the memb'ers in the opposite -direction being re vented b a ring or band 24 which is hel in position y a nut 25 screwing onto the outer end of the body portion. It will be observed ,that the sections or members of the bod portion are held' together by the walls of t e openings through the members of the arm, b rings or bands 23 and, 24 by the nut 25.. If] desired, a band or ring 26 ma shrunk or forced on the inner end o the body, thereby further reinforcing the body portion, as' against any tendency to separate the sectipns by force. The body portion of the hub when made in sections, is preferably locked to the shaft by two keys engaging grooves in the respective sections of the body portions.

I claim herein as my invention:

1. A propeller hub having in combinabody portion and a blade carrying arm consisting of two semicircular sections, said sectionsliaving openings therethrough intermediate their ends for the reception of the at their ends with means for positively engagin the Shanks of blades.

2. pro ller hub having in combination a tubular dy portion, a blade carrying arm consisting o two semicircular sections having their ends so constructed that when Y the sections arel placed together the Shanks ,of the blades will be positively gripped and having openings intermediate their ends for the rece tion of the body portion and means for hol ing the sections'together.

3.' A propeller hub having in combination a tubular body rtion provided with spaced seats; an arm or carrying the blades, said arm havin a transverse opening intermedi' ate its'en s for the reception of thebody portionthe walls-of'said opening being conotruod to 4si; tho y@om in the body portion l body portion and provided and means for preventing movement ofthe arm on they body portion.

. 4. A propeller hub having Vin combination with a tubular bod portion; an arm for carrying the propel er blades consistin r of two semicircular sections having openings intermediate their ends for' the reception of the body portion, said sections being internally recessed adjacent to their ends; blades provided with heads or enlargements adapted to (it in the recesses of the arm section and means for holding the sections together.

5. A propeller hub having in combination a body portion consisting of semicircular sections, and an arm for carrying the blades of the propeller having a transverse opening intermediate its ends whereby the 'sections of the body portion are held together by the arm.

6. 'A propeller hub having in combination a body portion consisting of semicircular sections; an arm adapted to carry the' propeller blades consisting of semicircular sections and having their ends for the reception ofthe body portion and,A means for holding the body and openings intermediate intermediate of their ends for the reception ofthe hub or bod portion and provided on opposite sides ofy said openings with recesses, blade Shanks adapted to be rripped by the arm sections and rovided wit lheads or enlargements adapte to extend into said l recesses in the arm sections and means for drawing said lsectionsagainst the Shanks.

In testimony whereof, I have hereunto set my hand. v

THOMAS A. DIcKs. 

